Question

A circle with a radius of 3cm sits inside a circle with a radius of 11cm. What is the area of the shaded region? Round your answer to the nearest 100th. NOTE: The larger circle is shaded ( the smaller circle isnt )

Answer 1

`A=351.68\ cm^2`

Explanation:

we know that

The area of the shaded region is equal to subtract the area of the smaller circle from the area of the larger circle

so

`A=\pi(r_b^2-r_a^2)`

we have

`r_b=11\ cm` ----> radius of large circle

`r_a=3\ cm` ----> radius of smaller circle

assume

`\pi=3.14`

substitute

`A=3.14(11^2-3^2)=351.68\ cm^2`